Laminated materials such as, for example, composites are widely utilized to increase structural rigidity in a wide variety of products. For example, composites are increasingly utilized by the airplane construction industry to build airframes, structural members of airframes, wings, wing spars, and the like. In some of the most advanced aircraft, where high strength and rigidity and low weight are extremely important, composites may account for a significant portion of the airframe as well as the external surface or skin.
Typically, these composites are constructed from a plurality of layers placed over a form. These layers are often referred to as partial or full plies. Each ply may be in the form of unidirectional fiber material, woven fibers in a fabric, braided, metal foils, or a variety of other conformations. In general, the unidirectional material, such as, “tape” may be place in any arbitrary orientation or angle. Plies of tape are often placed in several directions or strand orientations such as, 0°, 90°, ±45°, and the like. The fibers may be made from any of a multitude of natural and/or “man-made” materials such as fiberglass, graphite, Kevlar®, and the like.
To fabricate a composite item, a “layup” of plies is placed in or on a form or mandrel. These plies may be saturated or pre-impregnated with a resin such as epoxy. This epoxy may be cured or hardened in a variety of ways depending upon the particular epoxy system utilized. If any internal voids are present in the layup, these voids may adversely affect the cured composite item.
To minimize any voids present, the plies of the layup are typically place upon the mandrel with a roller that exerts a great deal of compaction force. Even with this compaction, some voids may remain. In addition, some resin systems may generate gasses as they are heated and/or during curing. While conventional methods and devices have been employed to overcome these issues, these conventional solutions have not been fully successful.
Accordingly, it is desirable to provide a system, apparatus and method for debulking a composite layup that is capable of overcoming the disadvantages described herein at least to some extent.